ABSTRACT Identifying effective strategies for reducing obesity is critical for alleviating the unequal burden of obesity and related adverse cardiopulmonary and sleep outcomes facing black and Hispanic women in the U.S. Studies typically focus on identifying independent effects of individual and environmental factors on obesity, but this approach overlooks important inter-relationships between these factors. This is challenging to model using traditional regression modeling approaches which are not well equipped to handle the complex ways individuals interact with their environments. Systems science approaches were promoted in two recent reports released by the Institute of Medicine and are part of the NHLBI Strategic Research Priorities because predictive and simulation-based models can both elucidate the complex inter-relationships between social, economic, and environmental causes of poor health and assess the benefits and harms of policy and intervention options. Thus, the overall goal of this application is to use a systems science methodology, agent- based modeling, to understand how individual-level behaviors and psychosocial factors interact with characteristics of the food environment to influence eating behaviors and obesity. This goal will be accomplished by executing the following aims: 1) to examine associations of food store characteristics with body mass index among Hispanic, black and white women; 2) to develop an exploratory agent-based model that simulates the emergence of racial/ethnic disparities in obesity among women; and 3) to investigate the effectiveness of potential multi-level interventions to reduce obesity. The candidate, Kiarri Kershaw, is an Assistant Professor of Preventive Medicine at the Northwestern University Feinberg School of Medicine. Her strong training in general epidemiology, social epidemiology, and population health has allowed her to pursue a research agenda focused on racial/ethnic, socioeconomic, and place-based disparities in cardiovascular disease risk factors. The K01 award will allow her to build on her current training by providing her with protected time to collect data on factors that influence lifestyle choices and to build and test an initial agent- based simulation. It will also allow her to learn how to work with community stakeholders and policymakers in order to develop research studies with a greater potential to translate into public health improvements. This training will help Dr. Kershaw achieve her long-term career goal of establishing an independent research program that focuses on how inter-relationships between individuals and their environments influence disparities in CVD risk.